[1]} select a sample of 17 FG candidates by combining XMM observations with SDSS DR7 data. They analyse the stellar populations of the BCGs of these systems using SDSS spectra and the Starlight code [2]}. Their results showed no significant differences in stellar star formation rates, age, and metallicities between FGs and their two control samples, one built by optically-selected BCGs, the other with X-ray-selected BCGs.
